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11 Cards in this Set
- Front
- Back
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The "greenhouse effect" often gets a --- because of its association with global warming, but the truth is -----. |
bad rap
we couldn't live without it |
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Life on earth depends on ----. About 30 percent of the sunlight that beams toward Earth is deflected by the --- and scattered back into ---. The rest reaches the --- and is reflected upward again as a type of slow-moving energy called ---. The heat caused by infrared radiation is absorbed by "greenhouse gases" such as ---4, which slows its escape from the atmosphere. |
energy from the sun outer atmosphere space planet's surface infrared radiation water vapor, carbon dioxide, ozone and methane |
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Although greenhouse gases make up only about 1 percent of the Earth's atmosphere, they regulate our climate by --- and -----. This phenomenon is what scientists call the "---." Without it, scientists estimate that the average temperature on Earth would be colder by approximately --- degrees Celsius (--- degrees Fahrenheit), far too cold to sustain our current ecosystem. |
trapping heat holding it in a kind of warm-air blanket that surrounds the planet greenhouse effect 30 54 |
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How Do Humans Contribute to the Greenhouse Effect? While the greenhouse effect is an essential environmental prerequisite for life on Earth, there really can be too much of a good thing. The problems begin when human activities ---and--- the natural process, by creating --- in the atmosphere than are necessary to ---. |
distort and accelerate more greenhouse gases warm the planet to an ideal temperature |
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Burning ---,--- and --- -including --- for automobile engines-raises the level of carbon dioxide in the atmosphere. |
natural gas, coal and oil -including gasoline |
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Some farming practices and land-use changes increase the levels of ---and---. |
methane and nitrous oxide |
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Many factories produce ---- that do not occur naturally, yet contribute significantly to the --- greenhouse effect and "global warming" that is currently under way. |
long-lasting industrial gases enhanced |
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Deforestation also contributes to global warming. Trees use carbon dioxide and give off oxygen in its place, which helps to create the ----. As more forests are logged for --- or cut down to make way for ---, however, there are fewer trees to perform this critical function. |
optimal balance of gases in the atmosphere timber farming |
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Population growth is another factor in global warming, because as more people use fossil fuels for ---3 the level of greenhouse gases continues to increase. As more --- occurs to feed millions of new people, more greenhouse gases enter the atmosphere. |
heat, transportation and manufacturing farming |
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Ultimately, more greenhouse gases means more ----, which gradually increases the temperature of the ----. The Average Global Temperature is Increasing Quickly Today. The increase in the Earth's temperature is increasing with --- speed. |
infrared radiation trapped and held Earth's surface and the air in the lower atmosphere unprecedented |
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To understand just how quickly global warming is accelerating, consider this:During the entire 20th century, the average global temperature increased by about --- degrees Celsius (slightly more than --- degree Fahrenheit). Using computer climate models, scientists estimate that by the year 2100 the average global temperature will increase by --- degrees to --- degrees Celsius (approximately --- degrees to --- degrees Fahrenhet. |
0.6 1 1.4 to 5.8 2.5 to 10.5 |
